我有一个用
Swift编写的应用程序,它从他们的地址簿中提取用户联系人.
我想过滤掉只包含公司名称的联系人(这样你就可以得到“假定的”真人联系而不是商家)
以下是我在app的Objective-C版本中实现的方法:
NSArray *allContacts = (__bridge_transfer NSArray *)ABAddressBookCopyArrayOfAllPeople(addressBook); NSPredicate *predicate = [NSPredicate predicateWithBlock:^BOOL(id person,NSDictionary *bindings) { NSString *firstName = CFBridgingRelease(ABRecordCopyValue((__bridge ABRecordRef)person,kABPersonFirstNameProperty)); NSString *lastName = CFBridgingRelease(ABRecordCopyValue((__bridge ABRecordRef)person,kABPersonLastNameProperty)); return (firstName || lastName); }]; NSArray *peopleNotCompanies = [allContacts filteredArrayUsingPredicate:predicate];
这很好用,所以这是我尝试在Swift中做到这一点:
var contactList: NSArray = ABAddressBookCopyArrayOfAllPeople(addressBook).takeRetainedValue() var predicate: NSPredicate = NSPredicate { (AnyObject person,NSDictionary bindings) -> Bool in var firstName: String = ABRecordCopyValue(person as ABRecordRef,kABPersonFirstNameProperty).takeRetainedValue() as String var lastName: String = ABRecordCopyValue(person as ABRecordRef,kABPersonLastNameProperty).takeRetainedValue() as String return firstName || lastName })
现在这有两个问题.我在return语句和谓词调用结束时收到这些错误:
如何在Swift中的ObjC代码中提供类似的功能?或者有更好的方法在swift中检查联系人是否只有公司名称,然后从最终数组中省略它?
谢谢!
解决方法
如果firstName和lastName是可选字符串,则可以将它们与nil进行比较,并在布尔表达式中使用它们.
你的第二个错误是由于关闭后额外的paren.这段代码应该有效.
var predicate: NSPredicate = NSPredicate { (AnyObject person,NSDictionary bindings) -> Bool in var firstName: String? = ABRecordCopyValue(person as ABRecordRef,kABPersonFirstNameProperty).takeRetainedValue() as? String var lastName: String? = ABRecordCopyValue(person as ABRecordRef,kABPersonLastNameProperty).takeRetainedValue() as? String return firstName != nil || lastName != nil }